Machine model evaluation and interconnect effect study for TMR HGA

This paper presents Machine Model (MM) discharge to TMR HGA in different ways, including stressing between the two read pads, and between one read pad and ground. The breakdown voltage is 0.89 V and 6.0 V respectively. The discharge voltage at the TMR sensor in MM stress test is measured and simulated for each case. The discharge voltage at the TMR sensor is inversely proportional to the interconnect window percentage in the later case. Increasing the window percentage in the reference plane can effectively improve threshold voltage of the TMR sensor when MM stressing between one read pad and ground.